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Pinewood Derby Time!

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OKTurbo

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Looks like I'll have to move the rockets off the building table for a while. It's Pinewood Derby time! My 8 yr old, Philip, recieved his PWD kit monday night at our annual "Blue&Gold" Cub Scout Pack Meeting. Time to start carving....once the "project manager" decides on a design.

We've gotten pretty good at this. My 12 year old, Timothy, has moved up to Boy Scouts, but we have 5 cars that he's built over the years. (from TigerCubs thru Webelos II). Philip is now a Bear Scout...awarded his Bear rank at monday's meeting, so this will be his 3rd PWD car. The building of Philip's Positron rocket was one of his achievements to Bear rank BTW.

My father (Papa to the boys) and I put a new rubbed tung oil finish on the track over the Christmas holidays this year. So we are ready to go!

Making memories....thought I would share...

John
 

cls

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we're doing a pinewood derby in the YMCA Adventure Guides this year. we don't know anything about it so I would be interested to hear some of your "secrets" to make it go.
 

WiK

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Could someone fill me in here. What is a pinewood derby?!?

I dont think we have them over here.

Phil
 

OKTurbo

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If you do a Google search for PineWood Derby you'll be surprised how much info is out there. For our Cub Scouts we try and keep everyone to the official BSA rules. In other words...no knife edge wheels...or funny wheel bearings. They must be built using the parts in the box and follow the official dimensions for height x length x width plus max weight.

The biggest tips are to take all the casting flash off the wheel's running surface. Polish the "nails" / axles to get any imperfections off them and load up on graphite or teflon dry lube. Make sure all the wheels are lined up good and straight. Some guys try to get it so that only 2 wheels...one in front and the opposite side on the rear are touching (less rolling friction). Add weight to get exactly 5 oz...take trim weights the night of the race for the official weigh-in so you can get 5 oz on the official scale.

Weight placement kinda depends on what track your club has. The official BSA track slopes at first then goes to a flat section for the final run to the finish line. If your track is like this....put the weight as far back as you can. This puts the CG higher up on the ramp when the car is on the starting line, giving you a longer run for acceleration.

If you have a flat, ramp style track that slopes evenly all the way from start to finish, weight placement really doesn't matter.

The point of the whole thing is to let the boys have fun building a car and working with their dad (or mom / grandparent / etc) on a project. I tend to let my boys do the lion's share of the building. The cars look good, but you can tell they were built by a kid. I've found that aerodynamics don't really have much to do with it...it's mostly in the wheel alignment and axle friction. We've had some pretty funky designs (like a hot-dog car) that have won.

Just remember...have fun...spend some time with the kids and be sure to have a talk with them before you start about winning/losing/sportsmanship. Don't allow a group of kids to cheer just one car on. Cheer for everyone. Shake hands after each race. It's easy for kids to get their feelings hurt. We even give out a "flat tire" award for the boy that loses all his races.

It's not about the winning and losing. It's about the memories you fill these kid's head with.

Have Fun,
John
 

powderburner

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Originally posted by WiK
Could someone fill me in here. What is a pinewood derby?!?
It's an American tradition.

It is a contest for children to teach a few craft and mechanical skills, and to encourage development of a little inventiveness and creativity.

You pay about $5 to whatever local organization is sponsoring the thing, and you get an 'official' kit that includes a block of wood for the body, a couple small nails for axles, and four little plastic wheels. You are not supposed to substitute anything for anything or you supposedly risk being disqualified. You can add lead weights to the cars to bring them up to regulation weight.

On race day, the sponsor will have a long slanted track set up on which the cars are raced 4 or 6 at a time. The starting gate is elevated a few feet and the track runs several yards down a flat slope until it hits bottom, and then runs horizontally several more yards. The cars are 'gravity powered' and are not allowed to include any propulsion devices. The cars all have separate lanes and so do not run into each other. Many tracks have electronic photocell timers at the bottom to determine the order of the finishers. Several heats must usually be run to get to an overall winner.

The kids are supposed to cut and shape and finish the body in some creative and stylish manner, and assemble the axles and wheels. Unfortunately, this is where the process goes badly wrong.

There are thousands (millions?) of frustrated fathers out there who remember being beaten at this contest when THEY were kids. So they take the kit away from junior and assemble it themselves, polishing the axles, trimming and sanding the molding flash from the edges of the wheels, and generally doing anything and everything they can to make sure that their kid wins. Strategies and construction tips are held secret, and are definitely NOT easily shared. In most cases, the kid experiences very little and learns nothing (except that Dad is nuts).

There are tons of websites, check 'em out. If I get a chance (and if I can find my kid's old cars) I'll take some pix and post them.
 

WiK

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Originally posted by powderburner
The cars are 'gravity powered' and are not allowed to include any propulsion devices.
So no rocket motors in 'em then! :p
 

vjp

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Pinewood Derby

Pronunciation: 'pIn-"wud 'd&r-bE
Function: noun

1 : a racing competition, in which young children with no prior woodfinishing, modeling, construction or painting experience produce finely crafted, superbly finished ultra-high-performance race vehicles with absolutely no help from their dads, honest.

2 : an annual event in which adults compete with one another, by proxy through their children.

:D


(For what it's worth, my own son did in fact build his himself, and they all looked it! I looked up all the tips and hints on the web and guided him using the bandsaw and my lathe, but he did the work himself)
 

powderburner

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Originally posted by WiK
So no rocket motors in 'em then!
The Derby police would be after you for sure!

Actually, I have always wanted to build one of those cars with an electric motor pulled from an old slot car, and a rocket motor, and a bunch of wound-up rubber bands------all purely for ballast, just along for the ride. And then sit back and wait to see what the judges would do about it.

vjp, I admire you for letting your kid do the work. I hope he won at least a few races?
 

Steward

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Same thing at my house...my 9yr old has his (and mine) first one this year....he just started scouts this year....
 

Frodo2801

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We had one of these sitting around the house from a few years ago and my sons straped a b6-5 on it with wire ties and sent it down the drive way. The thing went great for about five yards until one of the rear wheels let go and then it was on, it started doing loops and finally wound up in the bushes when the ejection charge went off it set the bush on fire, lucky I had a fire exstinguisher in my truck or mom would have been (upset) to say the least. :eek: :eek:
 

Neil

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Only B6-4s... Maybe B6-6s too, I am not sure. I sure wish we had a video of *THAT*!:cool: :cool: :cool: :cool: :cool: :cool: :cool:
 

graylensman

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Originally posted by vjp
Pinewood Derby

2 : an annual event in which adults compete with one another, by proxy through their children.

The Pack my son was in did it the smart way: they had an event that was open to EVERYONE in addition to the heats open only to the Cubs. This allowed the parents to build their own without hiding behind the pretext of helping their boys.

My son designed and built his own cars as well. They never performed at "top level", but that's nothing compared to the pride he felt watching his creations roll down the track. :)
 

Neil

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If I ever build a pinewood derby car, I am putting a 24MM motor mount and some fins on that sucker!:D

We did something similar to the pinewood derby in school one time... Mine was shaped and painted like a V2!:cool: It didnt win, however. It turns out that its best to leave as much weight as possible on it... It works better. If I were to do it again, I would just use the entire block of wood!:rolleyes:
 

Martin Vrstal

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Pinewood Derby...brings back great memories for me.

The year was 1973...I was 10. My Dad had done most of the work and I had given it an awesome paint job. I smoked all the competition that night and it was down to the final heat of the night. What a tense moment in history. The gate fell, the cars raced down the track, and my entry was triumphant.

Dad and I went on to the next Derby Meet...like the Regionals...and got spanked on the first or second run. Oh well great memories and great moments in Derby history.

Here's a pic of my trophy and Derby car of 1973. It's missing the axels and wheels but still a winner in my book.
 

DavRedf

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all purely for ballast, just along for the ride. And then sit back and wait to see what the judges would do about it.

Powder thats plain wicked HE HE HE :D :D
Why did'nt I think of that?

David
 

Neil

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Hehe. You should make sure you have the middle lane, and then have struts that go out 2 lanes to either side, with 25 grams of BP over each lane other than yours! It would detonate then as soon as it started moving, eliminating ALL competition!:D :cool: It would make a very big boom, too! a combined 100 grams of BP!:eek: :eek: :eek:
 

jflis

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ahh yes, i remember them days :) In fact, our local pack is still using the pinewood track and timer that I designed (IR-LED trip at the finish line)

I will see if I can find the photo's i have of our entries. The dads got *so* bad about the *competition*, that they finally had a separate contest just for the dads. it was great :)

As far as I know, I still hold the all time record on that track!
 

Neil

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Well, you designd the track... are you sure you didnt have a button you could press to make the track your car was on win?:p :p :p :p :p
 

jflis

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nope, it was just a study of aerodynamics and gravity fed dynamics. cool design, when I get a chance, i'll pop a picture of it up. I have it downstairs in my shop
 

powderburner

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I made this one with my daughter a few years ago. I did the rough wood working, she did most of the sanding. She did all the painting, and I helped with the stick-ons. She made it through several heats with this, and (if I remember correctly) placed something like third in her division.
 

powderburner

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Once a girl has been seen with a pinewood derby car, it just won't do to re-enter the same car the following year. So we put on our thinking caps and came up with this one. It made it through a few heats but didn't place. It DID get a special award for style (not styling, style).
 

powderburner

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My #1 son wanted to do something different, so we came up with a 'GameBoy' car. I can't find it right now, but it was just the basic wooden body block with the top 2/3 cut off. I cut a thin layer from the waste, split it in half, and glued it on the sides of the remaining body to make a wider flat-top. We then sanded the top smooth, and rounded the corners. Zachary painted the thing GameBoy Green, and painted on a screen and a bunch of buttons. We worked on the wheels and axles too, but after all that work, it didn't come close to placing. But I think he had fun building it.

My #2 son also wanted something different, and knew exactly what he wanted. Taxed my craftsmanship to get the thing rough-cut, but he sanded it the rest of the way and did the painting and decorating. Looks pretty cool, I think. This one ran pretty well but ended up not placing.
 

Fishhead

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I loved the idea of building and racing my own car when I was a cub scout, (I always painted mine Petty blue and STP red with a white 43,) but I really hated getting there and finding that a bunch of the other kids had their cars built by their dads in the shop. (Despite the fact that mine was hand carved with my Barlow pocket knife, I managed to take a second place ribbon home on one occasion, beating several of the dad-built entries along the way.) Now I have the displeasure of working with a couple of guys who are "into" building their son's derby entries, and spend a great deal of time and a fair amount of cash doing so. They were dying with anticipation over how fast the cars they'd built were and where they would display the trophy when they won, but the day after the race both were strangely silent. (Thankfully.) As it turned out, the kid who beat both of them built his car himself and didn't know to add any weight in to bring it up to the maximum allowable weight. His mom took him to the derby that night because his dad had to take his sister somewhere, and after the guy at the weigh-in table clued her in that the car would probably be too light to compete, she and her son hurriedly hot-glued quarters to the car to bring it up to the correct weight. They must have guessed right because when we worked cafeteria this week she brought in a picture of her son with the car and his first place trophy. His car looks like a sanded and gaudily painted block of wood with $1.25 or so in quarters strategically glued to it, but to him it's a Ferrari. There's nothing like the look on the face of a first grader who has just won against what are, for all intents and purposes, pro's. All he knows is that he won. He doesn't realize that he beat the best the internet had to offer. That's the way it oughta be. :D Great job, Eric. (Now if we could just get the scouts back into the rocket derby.)
 

OKTurbo

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We tried the rocket derby a couple of years ago. We actually did it for a few years. It was fun, but not nearly as popular as the PWD. The problem with the BSA rocket derby is there is so much prep that has to be done before each race. It made for some late nights with the little guys. We didn't like keeping the kids up 'til 10:00 on a school night. Plus all the holes in the action give the boys too much time to become disinterested in what was going on.

The BSA (Boy Scouts of America) Rocket Derby uses hollow balsa wood rockets with plastic fins and a hook/carrier on top. A plastic propeller and rubber bands are used to propel the rockets. Before each heat the boys have to wind up the rubber band...often breaking it while trying to get the maximum turns in it...this requires them to reload the rubber motor...etc...etc...
When you get the racers ready, the rockets are loaded up on wires that you string across the room. We had a starting device that held the rockets and kept the propellers from spinning, but I can't even remember exactly what it looked like.

It takes a lot of patience to run a Rocket Derby.

John
 

Chr$

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Ahhh. The Pinewood Derby. My other favorite hobby.

My son Just won first place for the third year in a row.

The attched pic is left to right Newest to oldest.

they finished first (New York), first (Vermont), first (Arizona), second (Vermont).

He builds more and more of the car himself every year.

The key to winning is attention to the axle polishing, wheel truing, and good placement on the track. Teach your son to line up the car perfectly and insist that they let him do it himself.

He's going to build a Barney Rubble log-car next year.

 

powderburner

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Originally posted by Fishhead
He doesn't realize that he beat the best the internet had to offer. That's the way it oughta be
I wish this happened more often. The group that my kids were working with had more than its share of competitive dads, to the point of being a**holes about the whole deal (and this was AT CHURCH!!!). Not the kind of environment I want my kids to experience?

One of the leaders told me that they had tried to run the contest with the cars impounded between building sessions. This was specifically to prevent dads from taking the cars home and sinking a hundred hours into them. Some of the dads were still insisting that they HAD to remove their cars from the class and take them home, for various reasons. This is pathetic.

Instead of a contest that is supposed to be fun, and for kids, it turns into a confusing disappointment (from the kids' perspective) where a whole bunch of them lose and don't understand why, and a few of them win and don't understand why. And a few dads strut around like they have really accomplished something.
 
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